Manufacture of dyestuffs



Patented Feb. 6, 1945 2,368,657' p F DYES TUFFS' Norman Hulton Haddock, Blackley, Manchester,

" England, assignor to Imperial Chemical IndustriesLin1ited, a'corporation of Great Britain NoDraWing; Application May 22,1942,.Serial Na The present invention relates tothemanufacture'of 'dye'stufis' 'andintermediates; therefor. According to the invention we" cause a ,pr-p'fchloride (made as described below) tointeract with a thi-ocyanoaryl-amine or an'N-mono-alkyl or -'aralkyl thiocyanoarylamine of the benzene series, thereby obtaining the corresponding di- (tlfiocyanosulphonarylamide). r v

The invention "also 'cOmpriSes'the steps of hydrolysing ap p -di"(6 -methylbenzthiazyl) a'zob'enzene-di(tliiocyanosulphonarylaniide) obtained in the above manner, to the corresponding p p"- di- (6 methylbenzthi'azyl)*azobenzene di mercapto sulphonaryla-rrfide) and oxidising thedaftter to the correspondingpolydisulphide.

The present 'polydisulphidesrepresent sulphurcon'tain ing dyestuifs which may be applied to cellulosic material from sodium sulphide solution according to the usual practice with sulphur dyestufi's. By- -this means thereare obtained bright orange-yellow shades possessing excellent :fastness l-to severe washing,- chemick and light.

The di(thiocyanosulphonarylam-ide) r derivatives of p zzp di(6emethylbenzthiazyli azobenzene referred-to abovepnot only constitute intermediates in the described manufacture of sulphur-containing :dyestufis but may themselves be phide :solut-ion.-according, to the usual :pract-ice applied to cellulosic material from :sodiiunsul-j withesulphur dyestuffs. Bythis procedurelrthedi(thiocyanosulphonarylamide) "derivatives" be comehydrolysed inv the sodiwn-sulphideso1u.-

.. tion to. the corresponding di(mercaptosvilphonarylamide) derivativea Thevlatter subsequently become oxidised toopolydisulphides on the, fibres. Thus by the dyeing technique commonly employed withsulphur dyestufis there are producedxon the. fibrevthe sulphur dyestuffs, to [the productionin.

substance of which the above-mentioned processes relatea In, this wayalso, dyeings are obn- -i tained having the properties already described. Accordingly,lthis invention is to beregarded as relatingflnotionlywto the manufacture by the aforesaid processesof sulphur-containing dyestiifisinsubstance but also, to their production onv the fibre, that lis on the cellulosic material directly, by employing-in the technique usual in dyeing with sulphurqdyestuffs, thesaboveinter mediate products, namely the di(thiocyanosu1- phonarylamide) -derivatiyes of pzp' -dfl fienethyl benzthiazyhazobenzene.

The starting material. whic methylbenzthiazyl) azobenzene. disulphonyl |chlo+ chlorr'd eifin a "solvent-Qsucheasiiloenzene.hrv o-di.

No; Eli-and :is given the constitution: .p: p" -di('6 methylbenzthiazyl 'azobenz'ene-o o -clisulplionic The disulpnonyl chloride derivatives used.

acidi'). as starting materials are accordingly two. innumber-"anri' difier'in'fconstitution.in respeet of positions occupied byjthe disulplionlyj -chloride groups' wh'idh positions. iilepend on whether 'ac'idiiis made'fby .(see

corresponding 'disulpholfi c above) process "(1) or "(2);;

-aralkyl"thiocyanoarylaanines of the bemzer'ie'.series there may be used, for instance,-p-thioc'yaiio- N-methylaniline, p thiocyanoaniline, p thiocyano oeaminoanisole, 2-:-5%dioh1ono-14:-ttiiocyanoaniline ror,p-thiocyano Nebenzyglaniliner The invention [is illustrated blitmotzrcon fined to the following, examples fine the;

partsiareby weight.

' Example! 7 m paptsof m;an naesthesiaea;

benzene disulphonyl chloride; (prepared; below); are .added to, 30K partsMof:molten p tmoe cyano-Nemethylanil-ineLand thefmixture stirred;

C. H0170. parts of; alcohol are iadded andithe; orange precipitate; is filtemed; and-.washed with: alcohol 11 pants"of: p:p'-di(6emethylbenzthiazyD azobenzene-difiN methyl -*4-;- thiocyanosulphon'an'ilidet are obtained. .i Thembove product: isildissolv'edfin 10D wager boiIi-ngaI-aloohol v taming f2'0 partsofusodiumesulphidecmstalsi- V Hydrolysis of the. diiNvmethylale-thiocyanosmeea p'honani'lid) derivativeito the'iconrespondihfirdi (N methyl-4emercapizosulphonanilide)l wiiat'ai"; s't'reamgo'f: air is passedithnougli di'(N minetl iylmercantosulphonanilide) v.

oxidised .therehy to the .icorres'pondinggm disule pliidegwh'ich is thrown db-wnia's'a precipitate; "Elie I dark brown powder, solublein concentrated 5111;. f phuric acid to give a bri-ht-orange-red solution;- I I i and n in il-w s-z e i mi lphide. to an rlde is madeby-treatirrglwithphesphoruspenta s-fl imshades-Whichl after oiddising-inthesairf areq pentachlorideand1150{parts of nitrobenzene are heated at 1-50-l55 C. for-2 hours. The solution is cooled and the precipitate which forms is, filtered, washed with benzene and dried. The product, p:p'-di (6-methylbenzthiazyl) azobenzene disulphonyl chloride, is a brown crystalline powder,

soluble in hot organic solvents to give bright yellow solutions. W l a Example 2 parts of p:p-di(6-methylbenzthiazyl)azobenzene disulphonyl chloride (made as described in Example 1), 5 parts of p-thiocyanoaniline and parts of dry nitrobenzene are heated together with stirring at 110-120" C. for 2 hours. The resulting melt is poured'into alcohol. The precipitate so formed is filtered and washed. wellwith alcohol. The product,. p:p'-di(6-methylbenzthiazyDazobenzene di(4-thio'cyanosulphonanilide) which is a yellowish-brown powder, is boiled for 4 hour with 50 parts of alcohol and 5"parts of sodium sulphide crystals, a brownish-yellow solution of the disodium salt of the corresponding p p'-di G-methylbenzthiazyl) azobenzene-di- (mercaptosulphonanilide) being obtained. This is diluted with water, and oxidised by' the addition of sodium m-nitrobenzene sulphonate at the boil until no more precipitation of the polydisulphide occurs. The bright'yellow suspension is filtered, washed with water and dried. This yellow powder dissolves indilute sodium sulphide solution, from which cotton is dyed in brownish-yellow shades, which on oxidising in air, become bright yellow. Y

' Example 3 L 10 parts of p:p-di(G methylbenzthiazyl)azobenzene disulphonyl chloride (made as described in Example 1), .10 parts of 2-methoxy-4-thiocyan'oanilineand parts of dry nitrobenzene are heated together, with stirring, at 130 C. for 2 hours. The mixture is diluted with 100 parts of ethanol and the brownish-yellow precipitate fil-.

tered'ofi and washed with ethanol and water.

The so-obtain'ed p p--di 6 -methylbenzthiazyl) azobenzene di (2-methoxy- 4 -thiocyanosulphonanilide) is hydrolysed by boiling with 100 parts of ethanol and 10 parts of sodium sulphide crystals for Ahour to the corresponding di(2-methoxy- Both the polydisulphide and the di(2'methoxyl-thiocyanosulphonanilide) dye cotton from aqueous sodiumv sulphide solutions ,in' brownish yellow shadeswhich on oxidising in the air become bright yellow. Theshades possess very,

good 'fastness. to severe washing, chemick and good fastness to light.

:Ea'ampZe4 Y 5 parts of p:p'-di(6-methylbenzthiazyl) benzene disulphonyl chloride (made as in Example 1),- and 10 parts of 2:5-dichlbro-4-thioicyanoaniline are heated with stirring at 135 C. for 2% hours. The dark coloured mixture is cooled to 90-100 and treated with 100 parts of ethanol. The brownish-yellow precipitate of dichloro-l-thiocyanosulphonanilide) is filtered ofi, washed with ethanol and waterand dried. The yellow powder dissolves readily'in boiling aqueous sodium'sulphide solution containing a little 'cellosolve, from which solution cotton is dyed in shades which after oxidation in the air, are yellow and possess very good fastness to severe washing, chemickand good fastness to light.

Example 5 5 parts of p:p-di(6-methylbenzthiazyl)azo benzene disulphonyl chloride (made as in Example 1), 10 parts of p-thiocyano-N-benzylaniline and 18 parts of dry nitrobenzene are heated v by the addition of sodium m-nitrobenzene sulphonate at the boil-as in'Example 2. The yellow precipitate of polydisulphide is filtered ofi, washed and dried. Itdyescotton (with airoxidation) in yellow shades of .Verygood fastness properties from boiling dilute sodium sulphide solutions. I Emample 6 V 5 parts of p:p di(6-methylbenzthiazyl)azobenzene disulphonyl chloride (made as described below), 10 parts of p-thio'cyanoaniline and 18' parts of nitrobenzene are .heated with stirring at 130-135 C. for 1 /2 hours.- After cooling to 90- 100 C., 200 parts of ethanol are added and the di(4-thiocyanosulphonanilide) filtered on and washed-with ethanol. I

The above -di(4-thiocyanosulphonanilide) is @The hydrolysed by'boiling with parts of ethanol and 5 parts of sodium'sulphide crystals for hour to the corresponding di(4'-mercaptos ulphon-' anilide) By oxidising the latter by the addition of sodium nitrobenzene sulphonate at the boil the corresponding polydisulphide is obtained asa yellow solid. Itis filtered off, washed with water and dried. It dissolves in dilute aqueoussodium" sulphide, from which solution cotton is dyed yellow shades, which become brighter on oxidation in the air and have good fastness properp: p -di G-methylbe'nzthiazyl) azobenzene disulphonchloride used above is preparedasf ollows: 10 parts of p:p'-di(6-methylbenzthiazyl);- azobenzene are added'to parts of 20% oleum during 10 minutes with stirringat 25 C." Stirring andis continued for 5 minutes 'andltl partsof 65% oleum are added. Thef'sulphonation mixture is stirred at 25 C. until a sampl is readily and completely soluble in dilute ammonia on shaking for 10-15 minutes) and pouredpn'tq ice. The: yellow precipitate of the sulphonic acid "is filtered off, washed with salt solutionj until free from acid and dried. 15 parts cums sulphonic i acid (passed through 100 mesh sieve), 100 parts of phosphorus pentachloride and 25 parts of phosphorus oxychloride are heated with stirring in an oil bath at 161-l65 C. for 3 hours. After cooling overnight, the pasty mass is added gradually to crushed ice. The precipitated sulphonchloride is filtered ofi, washed thoroughly with water and then with acetone and dried at 80 C.

Example 7 5 parts of pzpdi(6-methylbenzthiazyl)azobenzene disulphonchloride (made as described in I Example 6), 10 parts of p-thiocyano-N-methylj aniline and 18 parts of dry nitrobenzene are heated at 130-135 C. for 1% hours. The mixture is diluted with 200 parts of ethanoland the yellow solid (p: p-di(6-methylbenzthiazyl) azobenzene -di(N-methyl 4 thiocyanosulphonwith ethanol soluble in aqueous sodium sulphide, from which solution cotton is dyed in yellow shades, which become brighter on oxidation in the air and have good fastness properties.

Example 8 5 parts of p:p-di(6-methylbenzthiazyl)azobenzene disulphonyl chloride (made as described in Example. 6), 10 parts of p-thiocyano-N- benzylaniline and 18 parts of dry nitrobenzene are heated in an oil bath at 130-135 C. for 1 /2 hours. The dark coloured mixture after cooling to 90100 C. is treated with 200 parts of ethanol and the brown precipitate- (the N-benzyl-4- thiocyanosulphonanilide) filtered off and washed with ethanol and water. It is hydrolysed to the corresponding mercapto compound and the latter oxidised to the polydisulphide as described in Example 5. The polydisulphide dyes cotton from solution in aqueous sodium sulphide in yelbrownish-yellow precipitate filtered ofi washed with ethanol and water.

The above product (p:p'-di(6-methylbenzthiazyl) azobenzene-di(2 methoxy-l-thiocyanosulphonanilide)) is hydrolysed to the corresponding mercapto compound and oxidised to the poly:

disulphide as described in Example 3. It dissolves readily in boiling dilute aqueous sodium sulphide from which solution cotton is dyed in yellow shades of very good fastness properties.

1. Asulfur dye made by heating a p:p'-di(6-v methylbenzthiazyl) azobenzene di(4- thiocyanosulfonanilide) in a non-aqueous organic solvent with sodium sulfide until by hydrolization the corresponding di(4-mercaptosulfonanilide) is formed and then oxidizing until the corresponding polysulfide is formed.

2. A sulfur dyetmade by heating p:p'-di(6- methylbenzthiazyl) azobenzene -di(2-methoxy-4- thiocyanosulfonanilide) in a non-aqueous organic solvent with sodium sulfide until by hydrolization the corresponding di(4-mercaptosulfonanilide) is formed and then oxidizing uni 3. A sulfur dye made by heating p:p'di(6- methylbenzthiazyl) azob enezene-di (2- 5'-dichloro-" 4-thiocyanosulfonanilide) in a non aqueous organic solvent with sodium sulfide until by hydrolization the corresponding di(4-'mercapto sulfonanilide) is formedand' then oxidizing until the corresponding polysulfide is formed.

4. A sulfur dye made by heating p:p-di(6- methylbenzthiazyl) azobenzene di(4 thiocyanosulfonanilide) in a non-aqueous organic solvent with sodium sulfide until by hydrolization the corresponding di( l-mercaptosulfonanilide) is formed and then oxidizing until the corresponding polysulfide is formed. v p

5. The process of making a sulfur dye which comprises heating a p:p'-di(6-methyl-'benzthiazyl) azobenzene-oi(4-thiocyanosulfonanilide) with sodium sulfide in a non-reactive liquid. or-

low shades of very good fastness to severe washing, chemick and good fastness to light.

Example 9 5 parts of p:p'-di(6-methylbenzthiazyl)azobenzene sulphonchloride (made as described in Example 6), 7 parts of 2-methoxy-4-thiocyanoaniline and 18 parts of dry nitrobenzene are heated at 125-30 C. for 2 hours and then at 135-40 C. for hour. After cooling, the melt is treated with 200 parts of ethanol and the ganic solvent until the corresponding p:p-di(6- methyl-benzthiazyl) azobenzene-diUi mercaptosulfonanilide) is formed, and then adding water and an oxidizing agent until the corresponding polydisulfide is formed.

6. The process in accordance with claim 5 in which p:p'-(6 methyl benzthiazyl) azobenzene-di(2-methoxy-4-thiocyanosulfonanilide) heated with sodium sulfide.

7. The process in accordance with claim 5 in which p:p-(6 methyl benzthiazyl) afzobene zene-di(2-5-dichloro-4-thiocyanosulfonanilide is heated with sodium sulfide.

8. The process in accordance with claim 5 in which p:p-(6 methyl benzthiazy1)azoben-' zene di(4-thiocyanosulfonanilide) is heated with sodium sulfide and the organic solvent is alcohol;

NORMAN-HULTON HADDOCK.

and 

